JEE Main 2021 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 26 February 2021, Shift 1, Chemistry Q57

Question 57 of 90 in this shift, Chemistry question 27 of 30, Section B.

An exothermic reaction

\mathrm{X \rightarrow Y}

has an activation energy 30 kJ mol

^{-1}

. If energy change

\Delta E

during the reaction is

-

20 kJ, then the activation energy for the reverse reaction in kJ is __________. (Integer answer)

Official answer

NTA final key.

Chapter: Chemical Kinetics
Topic: Arrhenius Equation
Idea tested: Forward and Backward Activation Energy Relationship

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.